buildroot

xdriver_xf86-video-ati: needs dri3proto for glamor

We need to match xserver here, since we need glamor support there in
order to enable it here, hence need to match the dependencies.
For xserver it needs dri3proto+libepoxy, however if only libepoxy is
present then glamor would be disabled for the server but enabled for the
driver, leading to build failure.

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>